Hi @landofawz! As others suggested - when you click on ‘Add an attribute’, you will first notice a list of attributes that you can still reuse because they are still somewhere on the board, perhaps in another folder.
So, if you go to folder settings and click to delete from the whole board, they should not appear anymore.
The problem, however, occurs if you have deleted a whole folder but not the attributes themselves. The system still sees those attributes as a part of the board, and it gives you an option to reuse them.
If this is your problem, I strongly agree with you that this shouldn’t be happening and I have personally been trying to urge the dev team to give this some thought. However, it has not been prioritized yet as it hasn’t been reported by so many users as a problem actually.
So, I’ll try to keep pushing on this, but for now, I’ll have to disappoint you as it’s probably going to stay that way for a while longer.